Gene Transcription Profiles during Development of Mucosal Immunity

Avian infectious bronchitis virus (IBV) infection is a major chicken viral respiratory disease that causes significant economic losses to the poultry industry worldwide. The local mucosal immune response plays a vital role against the infection of this respiratory virus. Previous studies have indicated that a variety of innate immunity and a Th1 based adaptive immunity are activated in the host’s early defense (3 days post inoculation, dpi) against IBV invasion and they are responsible for the rapid clearance of virus from the local infection. In the present study, we propose to use IBV as a model system to uncover the molecular mechanism of mucosal immunity development by characterizing the kinetics of the local gene transcription profiles in trachea tissues after administration with an attenuated IBV strain (IBV-Mass). More specifically, immune-related gene transcription profiles in trachea at 1, 3, 5, 8, 12 and 21 days after the primary immunization and at 1 and 2 days after a second immunization were monitored using chicken 13K cDNA Microarray. Keywords: time course, cDNA 13k chicken array from FHCRC, IBV-chicken model The goal of the study was to uncover the molecular mechanism of mucosal immunity development using avian infectious bronchitis virus (IBV) as a model system. To achieve this goal, we monitored the kinetics of local gene transcription profiles in trachea tissues after administration of animals with an attenuated IBV strain (IBV-Mass) using chicken 13K cDNA Microarray. More specifically, immune-related gene transcription profiles in trachea at 1, 3, 5, 8, 12 and 21 days after the primary immunization and at 1 and 2 days after a second immunization were characterized. There are total 9 groups including 8 time points for vaccinated groups and 1 pooled age-matched control group. RNAs from each group were used to compare with RNAs from other four groups as determined by the loop-design. Four different RNA samples at each time point were used for hybridization with the respective four other groups. The use of loop-design allows the direct comparisons between the 9 groups, which would enhance the statistical power and lower the variation. This design is preferred over other methods when the goal of the study is to uncover the kinetics of gene transcription profiles.